







/J7f 

dALKINS, GRIFFIN & CO.’S 

Pinion §mnm Institute, 

HILLSDALE, MICH. 


j LIBRARY OF CONGRESS. Jlsog; 

and $ 


0 

IT* 


ntK51U5L 

JMJf ,T 


i a 


Ial "tUNITED STATES OF AMERICA. 

Oft]*- - 


,ed a 
.ence 
l the 
thus 


School will sustain, and the superior advantages 
afforded the youth of Michigan to acquire a thoroughly 
practical business education within their own State. 

HILLSDALE is a pleasant, active business place, 
having a population of about 3,500. It is situated on 
the S. M. & ]Sf. I. R. R., 66 miles west of Toledo, and 
is the seat of Hillsdale College, one of the most popular 
Colleges in the West, thus affording the same literary 
advantages to business students as at Oberdn, 0. 






DRAKE'S OBLIQUE GOLD PEN. 

Geo W. Bungay, the Poet and Associate Editor of the N. Y. 
Tribune, after fully testing the suprior merits of this Pen, vol¬ 
unteers the following : 

, DRAKES BUSINESS PEN. 

In the arbitrament of swords, 

The Soldier is the king of men ; 

But on the battle- field of words. 

The mightiest weapon is the Pen. 

Now in these piping times of peace, 

Let us the noblest record make ; 

Not with the pens of gabbling geese— 

But with the Business pen of Brake. 

Bit. Wm. Bunce, Oberlin, Military Surgeon for Lorain County* 
says :—“I had placed a high estimate on the value of your Ob 
lique Pen from the great reputation it had acquired in this com¬ 
munity, and now, after six months constant use of it in my office, 

I would not take twenty-live dollars lor this one it I could not 
get another like it. I consider it all that could be asked lor as a 
perfect pen.” 

A. H. Johnson, Esq., Cashier First National Bank, Oberlin, 
writes : “I have used one of the Brake Pens for the last year, 
and it is the best pen I have had in a long time. ” 

J. B. T. Marsh, Editor Lorain County News, says : “ My 

pen exactly suited me at first, and grows better on acquaintance, 
i do not want a better one, and have little confidence I couid find 
one if I did. 

The Assistant Cashier in the First National Bank of Pittsburgh, 
says: “I have a Gold Pen branded—“L. E. & W. A. Brake, 
Oberlin, Ohio,”—which 1 consider the best gold pen I have ever 
seen. 1 would like one more for my own use— fearing something 
may happen to the one I have. 1 could dispose ol one dozen to 
my friends if I had them.” 

One of eur former students, recently returned from the West, 
says “I have refused fifteen dollars for my Pen, which 1 have 
used two years.” 

There are imitations of the Oblique Pen—look out for all such 
_get offis bearing our names, and you will find it a good in¬ 
vestment. 

Price for Business Pen, Case and Holder, $5,00. Price ol La¬ 
dies’ Pen, Case and Holder, $4,50. Sent by mail post-paid. 

For wholesale prices, address L. E. k W. A. BRAKE, 

Principals Chirographic Bepartment, Business Inst. 




•AJNT OUTLINE 


OF 



AS PURSUED IN 

CALKINS, GRIFFIN & Co.’s, 

UNION BUSINESS INSTITUTE, 

OBERLIN, O: 


PREPARED BY 

CL 1ST. FOIsTID, .A.. IB., 

Instructor in Theoretical Telegraphy. 


OBERLIN, 0 : 

PUBLISHED BY CALKINS, GRIFFIN & CO. 
1 8 6 6 . 

V 





Entered, according to Act of Congress, in the year 1866, 
By CALKINS, GRIFFIN & Co., 

In the Clerk’s Office of the District Court of the 
United States, for the Northern District of Ohio. 



J. 13. T. MARSH, PRINTER. 



TO 


ALL HIS PUPILS, 

WHO, WITH EARNEST LABOR, AND IN PURSUANCE OP 
A LAUDABLE AMBITION, STRIVE TO MASTER AND 
ADORN 

THE PROFESSION OF THEIR CHOICE* 

THIS WORK 

IS AFFECTIONATELY INSCRIBED BY THEIR TEACHER 
AND FRIEND, 


THE AUTHOR 





IFIR/IEilF.A.aiE- 

This little volume does not claim to exhibit a 
complete view either of electric or telegraphic sci¬ 
ence. As indicated in its title, it presents simply 
an outline of these subjects; such an outline as may 
aid the student in preparing for recitation. 

The preparation of this work was necessitated by 
the fact, that though many volumes had previously 
been published upon telegraphy, yet none of them 
were found at once so brief, simple, and compre¬ 
hensive, as to answer the purpose of a text book in 
telegraphic schools. 

In the preparation of such a text book, two things 
demanded constant attention ; first, that the time 
which the telegraphic student can ordinarily devote 
to the theory of his profession is very limited, and, 
second, that such students are generally unacquaint¬ 
ed with science, many of tbem coming from the 
farm or shop without having obtained even a good 
common school education. For these reasons it was 
necessary that the statements of the work should be 
exceedingly concise, and yet clothed in language 
intelligible to the unlearned reader. Hence scien¬ 
tific terms and idioms have been generally discarded. 

The work covers only so much ground as the stu¬ 
dent can reasonably be expected to master, while 


Vi 


PKEFACE. 


pursuing a course in practical telegraphing ; it hav¬ 
ing been deemed better to attempt what could be ac¬ 
complished, than by attempting more, to accomplish 
less. For this reason many branches of electrical 
science have been omitted, as for example, thermal 
and magneto-electric induction, induction coils, 
magnetic properties of the earth, etc., etc. Bain’s 
and House’s Telegraph, and other American and 
foreign systems are also passed over in silence.— 
The lightning rod is briefly described, for the 
reason that besides being of great practical utility, 
it presents an application of some of the fundamen¬ 
tal principles of the telegraph. 

The method in which the work is composed (that 
oi questions and answers,) was chosen as being fa¬ 
vorable to conciseness of statement, and at the same 
time, best adapted to use as a text book. In the 
course of instruction pursued at Calkins, Griffin & 
Co.’s Union Business Institute, the work is largely 
accompanied with experiments and oral explana¬ 
tions, without which no text book, and especially 
one of this character, can fully accomplish its ob¬ 
ject. 

In the preparation of this u Outline,” much as¬ 
sistance hss been gained from the use of Prescott’s 
History, Theory, and Practice of the Electric Tele¬ 
graph, and similar works, for which the author’s ac¬ 
knowledgments are herewith returned. 


TABLE OF CONTENTS. 


PART I. 

ELECTRICITY. 

Section I. Electricity in General. 

Section II. Conductors, Insulation, and Induction. 
Section III. Electricity in Nature. 

Section IV. Frictional Electricity, and Instruments 
for Exciting and Retaining it. 

Section Y. Yoltaie Electricity and Means of Excit¬ 
ing it. 

Section YI. Magnetism. 


PART II. 

THE TELEGRAPH. 

Section YII. Relation of Circuits and Instruments. 
Section VIII. The Main Circuit. 

Section IX. The Local Circuit 
Section X. The Key. 

Section XI. The Relay. 

Section XII. The Register and Sounder. 



CONTENTS. 


viii 

Section XIII. The Relay Sounder ; General State¬ 
ments. 

Section XIY. Switches, Switchboards, Ground 
Wires and Lightning Arresters. 

Section XV. The Galvanometer, Rheostat Electric 
Variator and Repeater. 

Section XVI. Telegraphic Accidents. 

Section XVII. Atmospheric Electricity. 

Section XVIII. The Morse Telegraphic Alphabet. 


PART I.—ELECTRICITY. 


SECTION I. 

Electricity in General. 

To what does the telegraph chiefly owe its efficiency} 

To a natural agent called Electricity. 

What can you say of this agent? 

Its character is not well understood. Whatever ifc 
may he, it is supposed to pervade all nature. Until 
quite recently, it was considered a subtile fluid, but 
at the present day many eminent physicists regard 
it, not as a fluid, but as a form of motion. It is sup¬ 
posed by these philosophers to be nearly related to 
light and heat, consisting, like them, of waves or un¬ 
dulations, either in matter generally, or in a very 
subtile fluid or ether, which exists throughout the 
material universe. 

But though electricity is no longer considered a 
fluid by most philosophers, yet it is generally de¬ 
scribed in the language of the old fluid theory. 

What are the properties of electricity ? 

In its natural, unexcited state, electricity does not 
exhibit its properties, because in that state it makes 
no manifestation of itself whatever. 

(Unless, indeed, the universal phenomena of attraction 
and repulsion in their various forms be regarded as 
springing from this all pervading agent.) 


10 THEORETICAL TELEGRAPHY. 

When excited, it possesses the power of attraction 
find repulsion. 

In motion through living animal bodies, it occa¬ 
sions a contraction of muscles, accompanied by a 
peculiar sensation. 

Under certain circumstances it emits light, and 
..causes perceptible changes of temperature. 

Some, however, maintain that the light it exhibits is* 
caused by the agitation which it produces in the air, and 
that hence the emission of light is not a property of elec* 
tricitj'. 

It resembles heat in having no weight 5 but di - 
fers from it in not producing expansion in material 
substances. 

It also has a powerful effect in exciting chemical 
action. 

What two opposite hinds of electricity are there t 

Vitreous or positive, and resinous or negative. In 
8 , natural state, these two kinds always seem to be 
intermingled, thus neutralizing each other. 

It must be understood at the outset that the electrici¬ 
ties termed respectively positive and negative, do not 
sustain to each other the relation implied in those terms. 
That which is denominated negative is a positive or ac¬ 
tual power as really as the other. 

State the law of dedr iced attraction and repulsion. 

Like kinds repel and unlike kinds attract each 
other. 

What is fhe effect of separating the opposite hinds of 

electricity t 

It destroys the electrical balance or equilibrium 5 
and the separated electricities constantly attract each 
other, and tend to unite again. 


ELECTEICITY. 11 

When is a body said to be electrically excited , or electri¬ 
fied* 

When its positive and negative electricities are 
separated from each other. 

In causing this separation no new electricity is or 
can he produced. 

How is electricity otherwise divided t 
Into three kinds. 

1 st. Frictional or Static. 

2 nd. Chemical, Galvanic, or Voltaic. 

3d. Magnetic electricity, or Magnetism. 

In what respects do these several hinds differ ? 

They are supposed to differ, not primarily in thel. 
nature, hut in their manifestations or modes of ac¬ 
tion only. 

IIow is electricity manifested ? 

In its effects solely; and these are seen only when 
it is excited, that is, when it moves or tends to move. 
What general principle may be observed in regard to the 
direction of electricity in Motion f 
The positive and negative elements always seem 
to move simultaneously, and in opposite directions. 
At what rate does it move ? 

Its rate varies in different conductors, but in the 
best it approaches or perhaps exceeds the speed of 
light, viz., 192,000 miles per second. 

How is electricity developed by art f 

Chiefly in two ways ; by friction and by chemical 
action. It is also developed by several methods ol 
induction and by heat. 


SECTION IL 


Conductors, Insulation and Induction. 
When is a body said to conduct electricity ? 

When an electrical discharge passes over or 
through it. 

Bo all bodies possess equal conducting power? 

No, the conducting power of different substances 
varies in almost every possible degree, from the 
highest to the very lowest. 

Are there any substances which will not conduct at all ? 
Probably not. 

Explain the terms conductor and non-conductor. 

Those bodies are commonly called conductors 
which conduct readily, and those non-conductors 
which conduct slowly ; though strictly speaking, all 
bodies are conductors, and there are no non-con¬ 
ductors. 

Name the most, common and best conductors. 

Metals, water, charcoal, and animal bodies , but 
these differ much among themselves. Of metals, 
silver, copper and gold are the best; the two former 
conducting about five times as well as iron or plati¬ 
num. 

Mention the most common 'non-conductors. 

Glass, sulphur, resin, ice, silk, dry air, dry wood, 
varnish, porcelain, etc. 

Any of these substances, however, will conduct 


ELECTRICITY. 


13 


electricity when covered with moisture ; though, in 
that case, it is strictly the moisture that conducts, 
rather than the non-conducting substance. 

What is insulation ? 

The separation of a body from surrounding ob¬ 
jects in such a manner thatit can neither receive nor 
impart electricity. 

Sow is a body insulated? 

By being supported and surrounded by non-con¬ 
ductors. 

What is. the most common insulator? 

The atmospheric air. 

What is induction? 

It is the power which an electrified body has to 
develop electricity in a body not electrified, when 
the bodies in question are brought near together, 
but not sufficiently near for electricity to pass from 
one to the other. 

Sovj is induction accomplished ? 

By the power of attraction and repulsion, sepa¬ 
rating the electricities of the unexcited body ac¬ 
cording to the universal law, viz., likes repdl and un¬ 
likes attract each other. 

What takes place when the bodies causing and receiving 
induction are removed from each others influence? 
The latter usually returns to its original, unexcit¬ 
ed state. If, however, it be uninsulated before in¬ 
duction takes place, but insulated during the con¬ 
tinuance of the same, it will remain electrified even 
after the source of induction is removed. 


SECTION III. 

Electricity in Nature. 

We bavc seen that disguised or unexcited electricity 
pervades all nature. We will now consider some natural 
manifestations of it in an excited state. 

What is the most common and striking manifestation of 
electricity in nature ? 

The lightning. 

What is the lightning ? 

A discharge of electricity between two or more 
clouds, or between a cloud and the earth. 

Hovj is it caused? 

It is caused by opposite electricities accumulating 
separately, until their mutual attraction becomes so 
great that they overcome the resistance of the air 
and dart together. 

What produces the accompanying thunder ? 

The violent commotion of the atmosphere caused 
by the passage of the electrical discharge. 

3y whom and how was it discovered that lightning and 
electricity are identical f 

Benjamin Franklin made the discovery, and es¬ 
tablished it by raising a kite immediately before a 
thunder storm and drawing electricity from the 
clouds. 


ELECTRICITY. lt> 

Mention a second conspicuous manifestation of electricity: 
in nature. 

The Aurora borealis, or Northern light. 

What can you say of this phenomenon f 
It is not clearly understood. That it consists, 
however, of an electrical discharge in some form, is 
shown by the magnetic effects which always accom¬ 
pany it. 

Name some other natural exhibitions of electricity. 

Electrical sparks are often obtained on a cold day 
or night by brushing or combing the hair, or strok¬ 
ing the fur of a cat. 

Another exhibition of it is seen in the shock given 
by the electrical eel or torpedo. Also in the attract¬ 
ive power of the load stone or natural magnet, this 
power depending upon the presence of magnetic 
electricity or magnetism. 


SECTION IV. 

Frictional Electricity, and Instruments for 
Exciting and Retaining it. 

What is frictional electricity f 

It is that form of electricity which is generated by 
friction. 

Upon what substances is it excited f 

Upon non-conductors ; generally upon glass or 
sealing wax. 

May not electricity he excited by friction upon the surface 
of conductors ? 

It may ; but in that case it is instantly conducted 
away, and hence cannot be accumulated. 

What is the office of friction in exciting electricity ? 

It is simply to separate, mechanically or other¬ 
wise, the positive and negative elements previously 
existing in the substances employed. 

Mention a simple experiment illustrative of fnctional 
electricity. * 

If a piece of dry glass or sealing wax be briskly 
rubbed with woolen cloth, it will exhibit electrical 
effects. Small fragments of paper, cotton or other 
light substances, will be attracted to the excited 
surface, charged with electricity and then repelled. 

The experiment may easily be so varied as to il¬ 
lustrate many of the properties of the agent in ques¬ 
tion. 


ELECTRICITY. 17 

What instrument is employed in generating electricity 
for larger experiments ? 

The electrical machine. 

Explain its construction. 

It consists chiefly of four parts. 1st. A glass plate 
or cylinder suspended on an axle, and turned by a 

crank. 

2 nd. One or more rubbers, so situated as to press 
against the surface of glass. 

3d. A metallic body, called the prime conductor, 
so formed as to present a large amount of surface, 

and, 

4th. A set of sharp points connected with the 
prime conductor , but situated near the glass plate or 
cylinder, and pointing toward it. 

The rubber and prime conductor are insulated by 
being supported on posts of glass. The rubber is 
connected with a metallic ball of the same material 
as the prime conductor. 

Explain the operation of the machine. 

When the glass plate or cylinder is turned, posi¬ 
tive electricity is excited upon its surface by the 
friction of the rubber. This is carried around by 
the glass until it comes under the sharp points, 
which attract it and carry it to the prime conductor 
where it is accumulated. 

What is necessary in order to obtain any considerable 
charge ? 

It is necessary that the rubber should be connect¬ 
ed with the earth by some conductor, in order that 


18 THEORETICAL TELEGRAPHY. 

new supplies of electricity may be obtained, since 
that which naturally exists in the parts of the ma¬ 
chine is speedily exhausted. 

j How may negative electricity be obtained t 

By connecting the prime conductor with the earth 
and insulating the rubber with its ball. Negative 
electricity will then be gathered upon the latter by 
working the machine in the usual manner. 

Bow long is a charge retained by the prime conductor ? 

Not long ; though the time varies with the condi¬ 
tion of the atmosphere. But under the most favor¬ 
able circumstances, it gradually escapes, partly by 
reason of imperfect insulation, and partly through 
the surrounding air, by a process termed convection . 

What instrument is employed for retaining chargee of 
electricity ? 

The Leyden jar. 

Explain its construction. 

It consists of a glass jar coated inside and out 
with tin foil, except that a space around the top ia 
left uncovered for the purpose of insulating the two 
coatings from each other. A metallic rod surmount¬ 
ed by a ball passes through the lid and connects 
with the inner coating. 

Bow is the far chargedt 

By connecting the inner coating with the prime 
conductor and the outer with the earth. The two 
coatings are then charged with opposite electricities, 
the inner by conduction, the outer by induction ; the 


ELECTRICITY. 


former receiving its electricity from the prime con* 
ductor, and the latter from the earth. 

Why is a charge retained longer by the Leyden jar , than 
by the prime conductor f 

Because in the jar the mutual attraction of the 
opposite kinds of electricity prevents them from es¬ 
caping ; while in the prime conductor there is but 
one kind, which therefore constantly tends to diffuse 
itself by its own self-repulsion. 

How is the jar discharged ? 

By connecting its inner and outer coatings. The 
opposite electricities then rush together and neutral¬ 
ize each other. 

May the jar be charged in any other way than that above 
stated ? 

It may. The outer coatings may be connected 
with the prime conductor ; or when negative elec¬ 
tricity is gathered upon the rubber ball, either coat¬ 
ing may be connected with that j but in each case, 
when one coating connects with a part of the elec¬ 
trical machine, the other must with the earth. 

What general principle must be observed in using both 
the machine and the jar ? 

One part of each must always communicate with 
the earth in order to obtain a heavy charge. 

What is an electric or Leyden battery ? 

It is a combination of several Leyden jars, whos8 
inner coatings communicate with each other, and 
outer coatings the same. 


20 


THEORETICAL TELEGRAPHY. 


How is it charged and discharged ? 

In a manner similar to that in which the single 
jar is. 

What properties of electricity may he exhibited by expert - 
ments with the electrical machine and battery ? 

Its power of attraction and repulsion, induction 
and emission of light, its varied capacity for trans* 
mission over different substances, its power to give 
shocks, etc., etc. 

The Lightning Rod : Upon what principle is this rod 
constructed 7 

Upon the principle that sharp points receive and 
discharge electricity readily and in silence. 

How does it prevent the lightning stroke ? 

By allowing the opposite electricities of the clouds 
and earth to intermingle quietly and thus neutralize 
each other. 

What may be said of the efficiency of the lightning rod ? 

It is very great. It will discharge silently in a 
few seconds enough electricity to produce a powerful 
stroke if allowed to accumulate. 

It would seem at first glance that a conductor appar¬ 
ently so insignificant as a metallic rod an inch in diame¬ 
ter, could have little effect upon the electrical condition 
of vast thunder clouds. But the opposite is true. We 
must remember that the inconceivable speed of electricity 
upon such a conductor, enables it to discharge an im¬ 
mense quantity in a very short time ; also that since 
currents pass both ways simultaneously, and since for 
every atom of electrical force passing the rod, two atoms 
are neutralized, therefore, if a certain amount of electric¬ 
ity be transmitted by the rod from the cloud to the earth, 
four times that amount is neutralized and rendered pow¬ 
erless. The effect of the rod is thus multiplied. 


ELECTRICITY. 


21 


What is the best material for lightning rods 1 
Copper, that being the best conductor among com¬ 
mon metals. 

What particulars must be attended to in order that the 
rod may afford the desired protection ? 

The following : 

1st. It must be of sufficient size, viz., from three 
fourths of an inch to an inch in diameter. 

2d. If made in different parts they must be joined 
compactly together, so as to form one continuous 
conductor, 

3d. It must extend deep enough into the earth to 
reach moisture in all seasons of the year. 

-4th. It must be kept bright and sharp at the up¬ 
per extremity. This is accomplished by covering it 
with some metal not liable to rust, as gold, silver or 
platinum. 

How far from the lightning rod does its protective power 
extend 1 

Twice as far as the length of the rod above the 
building. 

What part of a building most needs protection ? 

The chimney, because the hot air and vapor aris¬ 
ing from it affords a ready passage for electricity. 
Barns newly filled with hay or grain need protection 
for the same reason. 

In genetral, what objects are most exposed to danger from 
lightning 1 

Elevated objects, especially those which are 
pointed upward. 


22 


THEOEETICAL TELEGEAPHY. 


To whom, are we indebted for the discovery of the light 
ning rod ? 

To Benjamin Franklin. 


SECTION V. 


Voltaic Electricity and the Means of Excit¬ 
ing It. 

What land of Electricity is employed in the Telegraph ? 

Chemical, or Galvanic, or Voltaic Electricity. 
How is it developed ? 

By chemical action. 

What is Galvanism or Voltaism ? 

That branch of science which treats of this form 
of electricity. 

How does Voltaic differ from Frictional Electricity 1 
It is less intense or energetic than the latter. 
Electricity may vary both in quantity and in intensi¬ 
ty. There may be a large quantity of it with low in¬ 
tensity, or vice versa. To illustrate ; suppose we have 
one hundred atoms of electrical force, each possessing 
an energy which we will represent by the numeral 1 ; 
suppose, again, that we have one atom with an energy 
represented by 100 on the same scale ; in the former 
case, quantity predominates, in the latter intensity. 

It is obvious that quantity and intensity may be com¬ 
bined in an endless variety of proportions. 

As these electricities are developed by art , what differ¬ 
ence is there in their manifestation ? 

Voltaic electricity discharges itself in a steady 
flow, while frictional, on the other hand, acts abrupt¬ 
ly and instantaneously. 

This difference results, undoubtedly, from the manner 
in which art excites the agents in question, and not from 
any inherent peculiarity possessed by them. 


24 


THEORETICAL TELEGRAPHY. 


It is the steady movement of the Voltaic current that 
adapts it to the purposes of the telegraph. 

What must be the arrangement of the conductors upon 
which Voltaic electricity moves t 

They must be arranged in an unbroken series 
called a circuit. 

What contrivance is employed in developing Voltaic Elec - 
tricity ? 

The Galvanic or Voltaic battery. 

There are many forms of battery, but we shall here be 
able to consider only three, viz., the most simple form, 
commonly called the simple Voltaic circuit, and the two 
forms generally employed in main and local telegraph 
offices. The explanation of these, however, will embrace 
all the fundamental principles of other forms. 

What arethe essential parts of a Voltaic battery ? 

Two dissimilar conductors and a liquid. These 
must be so related that the liquid will act chemically 
upon at least one of the conductors, and that if it 
acts upon both, it will affect them differently. 

A battery may be formed by a combination of 
two dissimilar liquids with one solid conductor. 

What conductors are commonly employed ? 

Metals, and among them, copper, platinum and 
zinc most frequently. Recently, solidified carbon 
also is largely employed. 

What liquid ? 

Water, with sulphuric or nitric acid. 

State the chemical constitution of these substances. 

Water is composed of on© equivalent of oxygen 
and one of hydrogen, 


ELECTRICITY. 2& 

Sulphuric acid is composed of three equivalents 
of oxygen and one of sulphur. 

Nitric acid contains five equivalents of oxygen 
and one of nitrogen. 

Sulphuric acid ia always combined with one equiva¬ 
lent of water. 

How may a simple Voltaic circuit be formed ? 

By placing in a vessel of water mingled with a* 
little sulphuric acid, a slip of copper and another of 
zinc, and making a conducting connection between 
them. 

How may this connection be made ? 

By bringing the metal3 into contact, or by pass^- 
ing a wire or other conductor from one metal to the 
other. The latter is the usual method. 

Why is this connection between the metals necessary ? 

Because without it there is no action. 

What substances are affected in the primary action of 
such a circuit ? 

The zinc and water only are affected.. 

Of ichat is water composed ? 

Of two gases, oxygen and hydrogen. 

Explain the chemical actions of the battery. 

As soon as the metals are connected, the water 
begins to be decomposed, and the zinc dissolved 
particle by particle. The zinc unites with the oxy¬ 
gen of the water, forming oxyd of zinc, and the 
hydrogen is set free and escapes. 

What is tlie electrical effect of this process ? 

When chemical action begins, the positive and 


28 THEORETICAL TELEGRAPHY. 

negative electricities are separated at the surface of 
the zinc, and pass, one to each metal. From the 
latter, they proceed in opposite directions over the 
conductor between the metals, until they reach the 
starting point, viz., the zinc surface, when they unite 
again. This process is incessantly repeated until 
the chemical forces of the battery are exhausted.— 
Thus there are two currents of electricity constantly 
acting in opposite directions. 

The electrical forces are here spoken of as being sep¬ 
arated and united at the surface of the sine. In reali¬ 
ty, however, this process occurs in every particle through¬ 
out the circuit. Still the above language may be re¬ 
garded as sufficiently exaot in view of the two conside¬ 
rations following : 

1st. Though eleclrical aotion takes place in every 
part of the circuit, yet it is developed or originated in 
the particles at the zinc surface, while other partioles 
throughout the circuit simply transmit it. The former 
are active, the latter passive. The former might be call¬ 
ed motive, the latter transmissent particles. 

2d. The expression “ a current of electricity ” de¬ 
notes properly a passage, not of matter or substance, but 
of force or motion. 

What then is the ojfice of the conductor between the met¬ 
als in this and every form of battery ? 

It is simply to furnish to the separated electrici¬ 
ties a channel by which they may unite again ; or 
in other words to restore the electrical equilibrium 
which the chemical action of the battery has de¬ 
stroyed. 

{State the electrical relations of the metals of.the circuit . 

Copper as compared with zinc is electro-negative 
•and hence attracts the positive current. Zinc acts 
in an opposite manner. 


ELECTRICITY. 


27 


This is not always true. If strong ammonia, for in¬ 
stance, were used instead of dilute sulphuric acid, the 
electrical relations of the metals would be reversed.— 
The universal rule might be stated as follows: that met¬ 
al which is affected by the primary action of the batte¬ 
ry is electro-positive within the liquid, and hence affords 
a negative current. 

Which current , then , does each metal furnish to that part 
of the circuit which is exterior to the liquid ? 

Copper yields a positive and zinc a negative cur¬ 
rent. The former is therefore called the positive 
and the latter the negative pole of the circuit or 
bhttery. 

What general principle holds true in regard to the poles 
of every Voltaic battery ? 

That metal which is electro-negative attracts the 
positive current in the liquid and hence is termed 
the positive pole, and vice versa. 

May several cups like the one just described be united in 
one battery ? 

They may ; and the effect thereby is greatly in¬ 
creased. 

What principle must be universally observed in making 
battery connections for telegraphic purposes t 
Positive poles must connect with negative, and 
negative with positive. 

Why might not a battery of simple circuits of this de¬ 
scription be employed on telegraphic lines ? 

For two reasons. 

1st. The zinc surface is quickly coated with the 
oxyd formed by its combination with oxygen. 

2nd. The liberated hydrogen adheres in bubbles to 


28 THEORETICAL TELEGRAPHY. 

the copper plate preventing in a great degree its con¬ 
tact with the water. 

By these causes, the action of the circuit is speed¬ 
ily interrupted. 

Daniell’s Battery. 

What battery is used in heal telegraph offices t 
Daniell’s constant battery. 

What is said in general of its construction ? 

It is formed upon the same principle as the simple 
Voltaic circuit already described. It is more com¬ 
plicated, however, being designed to produce a con¬ 
stant and steady current. 

In what respect does it differ from the simple Voltaic cir¬ 
cuit f 

Chiefly in two respects, viz : 

1st. The copper and zinc are separated by an 
earthen cup so porous that chemical actions can 
take place through it. 

2nd. The sulphuric acid is supplied not in its 
own proper form, but in combination with oxygen 
and copper in the form of blue vitriol, or sulphate 
of copper. 

Of what is blue vitriol composed ? 

Of sulphuric acid and oxyd of copper. 

What is oxyd of copper ? 

It is a compound of oxygen and copper. 

What metals are employed in DanielVs Battery t 
A hollow cylinder of sheet copper, and a solid bar 
of amalgamated zinc. 


ELECTRICITY. 


29 


What liquid ? 

Water saturated with blue vitriol. 

Explain the arrangement of this battery. 

It is divided into two parts by the porous cup. 
Within this cup are placed the bar of zinc and pure 
soft water ; without it the copper cylinder and water 
containing vitriol. The whole is generally enclosed 
in an earthen jar capable of holding about a gallon. 

This is the common arrangement on telegraph lines. 
Bat for laboratory purposes acidulated water is usually 
employed in the porous cup. 

The chemical processes in this battery are too compli¬ 
cated to be well understood except by the student of 
chemistry. We will give here the results simply. 

In DanielVs battery what becomes of the zinc ? 

It is dissolved particle by particle and combines 
with the oxygen of the water forming oxyd of zinc. 
What becomes of the oxyd of zinc f 
It remains in the water of the porous cup (though 
not without change,) until it is removed by clean¬ 
ing the battery. It darkens the water, and if allow¬ 
ed to accumulate, it finally settles in a dirty mass to 
the bottom of the cup. 

Some of it, at least, forms sulphate of zinc by uniting 
with the sulphuric acid which penetrates the porous cup 
after being liberated from the sulphate of copper in the 
outer vessel. 

Is the copper affected ? 

It is not affected by that action which produces 
the current, but there are accompanying processes 
which gradually consume it so that it must occa¬ 
sionally be renewed. 


so 


THEORETICAL TELEGRAPHY. 


Sow is the blue vitriol acted upon 1 
It is decomposed ; the sulphuric acid it contains 
is liberated in sufficient quantities to keep the bat¬ 
tery in action and its copper is set free and thrown 
down in fine particles. 

What is the use of the porous cup ? 

To keep this fine copper from covering the zinc 
and thus interrupting the action ; also to prevent 
the oxyd of zinc from mingling with the vitriol water 
outside the cup. 

Why does not hydrogen gas adhere to the copper cylinder 
and retard the action as in the simple circuit ? 
Because oxygen liberated lrom the oxyd of copper 
in blue vitriol unites with it forming water. 

Grove’s Battery. 

What battery is used in main telegraph offices ? 

Grove’s battery. 

Sow does its power compare with that of DamelVs ? 

It is much greater. 

What is said of its construction t 
It is based upon the same principles as Daniell’s, 
though differently arranged. Generally it employs 
two liquids instead of one and is therefore more dif¬ 
ficult of management. 

What metals does it employ f 
A thick hollow cylinder of amalgamated zinc and 
a slip of platinum leaf, the latter taking the plaee of 
copper in other batteries. 

What acids t 


ELECTRICITY. 


31 


Sulphuric and nitric. 

How is it arranged f 

Inside the porous cup are placed the slip of plati¬ 
num and strong nitric acid, outside of it are the zinc- 
cylinder and dilute sulphuric acid. 

The chemical reactions here are even more complicate 
ed than in the former case, and as before, we must satis¬ 
fy ourselves by giving results simply. 

Wliat parts of this lottery are acted upon in its chemi¬ 
cal processes ? 

Zinc, water, and nitric acid only. 

How is the zinc affected ? 

It is dissolved and forms with the oxygen of water 
oxyd of zinc, which combines with the sulphuric- 
acid and produces sulphate of zinc. 

What becomes of the nitric acid ? 

A portion of its oxygen combines with the liberat¬ 
ed hydrogen forming water. Of the remainder, a 
part escapes in the form of a gas, and part is left in 
a liquid state, gradually changing color, first to a 
reddish brown, then to a green, and finally becomes 
unfit for use. 

Are two adds always employed in this battery when used* 
upon telegraph lines 1 

No ; many lines employ one acid only, using it 
inside the cup, and pure soft water outside. 

Why is this arrangement preferred ? 

Because it is more easily managed and yet fur¬ 
nishes a current sufficiently powerful for telegraphic' 
purposes. 


"32 theoretical telegraphy. 

In the simple circuit and both batteries mentioned, what is 
the office of the sulphuric acid f 
It is to excite chemical action among the other 
agents present, although it does not seem to enter in¬ 
to any of the processes itself. 

In these batteries , which metal always constitutes the 
negative pole f 

Zinc, while copper and platinum are positive. 

Is it necessary that the circuit of a Voltaic battery be in¬ 
sulated ? 

It is only necessary that one half of it he insula¬ 
ted from the other half; or more exactly, there must 
he such insulation as will prevent all cross commu¬ 
nication between different parts of the circuit. 

May the earth be taken as apart of the circuit ? 

It may, provided the other parts be properly insu¬ 
lated from the earth. 

What relation does the telegraph line sustain to the bat¬ 
tery or batteries which work it ? 

It is simply a part of the conductor between the 
i>attery poles. 

A new form of battery has been recently invented and 
substituted upon some lines for Grove's.. It employs 
-bars of carbon or “cokes,” instead of platinum slips.— 
And in the porous cup, in the place of nitric acid, it 
makes use of a liquid termed “electropoion fluid,” com¬ 
posed of sulphuric acid and bichromate of potash. 

This battery is much cheaper than Grove's and emits 
no poisonous or offensive gases. 

Magnetism. 

What is Magnetic Electricity or Magnetism ? 


ELECTKICITY. 33 

It is that form of electricity which is seen in the 
magnet or load stone. 

All eleotricity consists of force. Magnetism is that 
variety of force which is directive or polar. Any sub¬ 
stance affected with it has two points called poles, 
which sustain opposite relations of attraction and re¬ 
pulsion to any other substance similarly affected. 

What are the properties of the magnet ? 

They are as follows : 

1st. The power of attracting and repelling other 
magnets. 

2nd. The power of attracting iron, steel and some 
other substances. 

3rd. A directive property, or the power to take a 
direction north and south when freely suspended. 

4th. The power to cause certain electrical changes 
in adjacent bodies. 

These are reduced by a careful analysis to the simple 
properties of attraction and repulsion. 

What ts the bad-stone or natural magnet f 
A native iron ore (protoxyd of iron,) which is 
found to possess magnetic properties; 

What is an artificial magnet f 
A bar ot iron or steel which ha3 acquired similar 
properties by artificial means. 

What are the poles of a magnet ? 

Two points which possess the greatest power. 

What names are applied to these poles t 
The one which points north is called the northern 
and the other the southern pole. 

State the law of magnetic attraction . 


3 


34 THEORETICAL TELEGRAPHY. 

Like poles repel and unlike poles attract each 
other. 

Wliat are those substances termed which are capable of 
acquiring magnetism f 
They are termed magnetics. 

Name the leading magnetics. 

Iron, steel, cobalt and nickel. The latter, howev¬ 
er, are capable of magnetism in a very low degree 
only. 

It is maintained by some that all bodies are either at¬ 
tracted or repelled by the magnet. Those which are at¬ 
tracted are themselves capable of becoming magnetic in 
some degree, and hence are called magnetics, while the 
other class are denominated diamagnetics. It is found 
that magnetics when exposed to the influence of a mag¬ 
net tend to take a direction parallel to its axis, i. e., the 
line joining its poles, but diamagnetics, on the other 
hand, incline to a direction at right angles with that line. 

When is a substance said to be magnetized ? 

When it has acquired magnetic properties. 

Now may a bar of iron or steel be magnetized ? 

In three ways. 

1st, by contact with one or more magnetic poles, 
2nd, by friction with the same, 

3d, by the inductive influence of currents of elec¬ 
tricity. 

In the method first named, what ‘principle is to be ob¬ 
served ? 

Each pole induces opposite polarity next to itself, 
and the same polarity at a distance. 

Explain the method by friction. 

The bar to be magnetized must be rubbed by or 


ELECTRICITY. 


35 


upon a pole of one or the poles of two magnets, If 
both a north and a south pole are used in the same 
operation they must move over the bar in opposite 
directions ; but the direction of the same pole must 
not be changed. 

How is magnetism, induced by a current of electricity? 

By passing it in a spiral coil around the bar to be 
magnetized. Such a coil is usually made of wire in¬ 
sulated by being covered with silk or some other non¬ 
conductor, and is called a helix. A magnet produc¬ 
ed in this way is termed an electro-magnet. 

What is residual magnetism ? 

When iron or steel i3 in contact with an electro* 
magnet, there will be a slight adhesion even after 
the magnetizing current ceases. But when this ad¬ 
hesion is once broken, it disappears entirely. This 
slight remnant of attractive power is called residual 
magnetism. It must be carefully observed that it 
affects only bodies in contact. 

Where are electro-magnets most usefully and extensively 
employed 1 

In the telegraph. To them it mainly owes its ef¬ 
ficiency. 

The common systems of telegraph depend entirely up¬ 
on the electro magnet. 

How is soft iron affected by magnetism ? 

It receives and parts with it readily. Indeed, mag¬ 
netism may be produced and destroyed in soft iron 
several thousand time3 in a second. 

Is hard iron or steel similarly affected ? 


36 


THEORETICAL TELEGRAPHY. 


No ; they are magnetized slowly, and retain mag¬ 
netic properties permanently. For this reason, arti¬ 
ficial magnets are made of steel. 

What takes place when a magnet is broken ? 

Each part becomes a new magnet with two poles 
of its own. 

Is it possible to obtain a magnet with one pole only ? 

It is not. 

Experiment renders it probable that the opposite po- 
larites reside in every particle of a magnet; that mag¬ 
netic induction separates the pre-existent electricities of 
each particle, but prevents their passing from one parti¬ 
cle to another. In the case of soft iron, as soon as the 
inducing cause is removed the separated electricities in¬ 
stantly unite again, by their mutual attraction, but in 
the permanent magnet they remain separated. 

# According to this view, a common magnet is a collec¬ 
tion of millions of infinitesimal magnets, and the poles 
of the former owe their power not to any force inherent 
in themselves, but to the combined action of the forces 
residing in the myriads of magnetic particles. 

Sow is a magnet affected by use? 

It increases in strength by use until it reaches its 
highest power. 

How may a magnet be made to lose its properties ? 

By heating, by violent blows, by disuse, or by 
'friction or induction, the opposite to that which de¬ 
veloped its magnetism. 

In reality, neither heat nor blows tend in themselves 
to produce or destroy magnetism. The state of molecu¬ 
lar agitation which they produce seems favorable to a 
change of magnetic state. Accordingly, it is found that 
bodies are more easily magnetized while subjected to 
their influence, and it is probable that under the same 
influence magnetism is destroyed simply by the attract¬ 
ion of the separated electricities in each particle. 


ELECTRICITY. 


37 


What is a horse shoe or U magnet ? 

An artificial magnet bent in the form of a horse 
shoe or letter U. 

What is the armature of such a magnet t 

A bar of iron or steel of a form suitable to be ap. 
plied to its poles. 

When is a magnet said to he armed ? 

When its armature is applied. 


PART 2.—THE TELEGRAPH. 


SECTION VII. 

Relation of Circuits and Instruments. 

How many classes of circuits are there upon a common 
telegraph line ? 

Two ; Main and local. 

Define each . 

The main circuit is that which extends the entire 
length of the line, of which the telegraph wire from 
station to station forms a part. 

The local circuit is a short one confined to the of¬ 
fice where it is used. 

How many of the latter are there on a line ? 

As many at least as there are offices and some¬ 
times there are more. 

What battery is used upon each circuit ? 

Grove’s upon the main, and Daniell’s upon the 
local. The former is hence called the main, the lat¬ 
ter the local battery. 

When is a person said to break or open , and when to 
close circuit 1 

A person breaks or opens circuit when he inter¬ 
rupts communication so that the electrical current 
ceases. He closes when he restores communication 
again. 


THE TELEGRAPH. 39 

What instruments are commonly employed in trans¬ 
mitting and receiving messages ? 

The key, register or sounder, and relay. 

With which circuit is each connected ? 

The key with the main, the register and sounder 
with the local, and the relay with both. 

What is the office of the hey f 
To open and close the main circuit. 

What of the main circuit ? 

To operate the relay. 

What of the relay ? 

To open and close the local circuit. 

What of the local circuit ? 

To operate the register or sounder. 

Explain then, in brief the relation of the various instru¬ 
ments and circuits. 

The key opens and closes the main circuit, the 
main circuit operates the relay, the relay opens and 
closes the local circuit, and the local circuit operates 
the register or sounder. 


SECTION VIII. 

The Main Circuit. 

Of what is the main circuit composed ? 

Chiefly of the following parts. 

1st, The metals and liquids of the main batteries. 
2nd, The telegraph wire from office to office. 

3d, A loop from this wire passing into each of¬ 
fice and including the key and relay helices. 

4th, The earth. 

What hind of wire is employed for the line ? 

Iron wire commonly of sizes 8 and 9. This wire 
should be galvanized or coated with zinc to protect 
it from rust. 

Although copper is a better conductor than iron yet r it 
is more costly and not so strong, hence the latter is used 

Sow is the main Tine insulated from the earthf 

By being supported in the air upon poles by insu. 
lators made wholly or in part of glass or some other 
non-conducting material. 

What is said of the construction of these insulators f 
They are made in a great variety of forms. A 
common form, known as the Wade Insulator, con¬ 
sists of a glass cup inverted upon a wooden bracket 
and covered with a cap made of baked wood boiled 
in tar. This cap sustains the wire and also protects 
the glass in a great degree from rain and moisture, 
thus increasing the efficiency of the insulator. 


THE TELEGRAPH. 


41 

This insulator, like all others, is open to several ob¬ 
jections. Its chief deficiency lies in the fact that, not¬ 
withstanding the protection of the wooden cap, the glass 
is still liable in damp weather to be covered with a film 
of moisture which furnishes the current a means of es¬ 
cape. 

Explain the insulation of loops from the main wire lead¬ 
ing into offices. 

Their insulation is affected by covering the wire 
with gntta percha, silk, cotton, or some similar non¬ 
conductor. 

How do the extremities of the main line connect with the 
earth ? 

By means of ground wires. 

How many main batteries are required upon a line ? 

Generally two, one at each terminus ; but short 
lines sometimes employ one only ,- and very long 
lines require more than two, the additional ones be¬ 
ing stationed at intermediate points. 

How many Grove cups are needed for a hundred miles'] 
From five to fifty, according to size and quality of 
wire, completeness of insulation, etc. Probably 
about thirty is the average number. 

In connecting main batteries with the line , what rule 
must be observed f 

Like poles must never be connected. The wire 
leading from the positive pole of one battery must 
join the negative of the next, and the positive pole 
of one and the negative pole of the other terminal 
battery must connect with the earth. 

Where several lines diverge fron one battery is it necessa- 


4:2 


THEORETICAL TELEGRAPHY. 


ry that each should have a terminal battery of its own'l 
No. One such battery, provided it be of sufficient 
power, will operate all of them by division of current. 

By this arrangement, a great saving is effected, for it 
is a singular fact that a battery sufficient for one line 
will work several with equal facility, provided there be 
not too great a difference in their lengths. Practically, 
the limit to variation in length may be stated as follows: 
Of the several lines operated from one battery either may 
be long or short as desired, without reference to the 
length of the others, provided none of them extend less 
than fifty miles, and provided also, that if either line 
fall short of that distance, there be introduced into its 
.circuit a rheostat (See Sec. XIV,) of such resistance that 
line and rheostat together shall offer a resistance equal 
to that of fifty miles of common line wire. 

How does the main current afford communication between 
distant places ? 

By controlling the operation of relay instruments 
in all those places. Thus a person at any part of 
the main circuit can, by opening and closing it, di¬ 
rect the action of the relays throughout the entire 
circuit, though it extend several hundred miles. 

Circuits three or four hundred miles long are not un¬ 
common, and in a few instances single circuits have 
been worked through a distance of nine or even twelve 
hundred miles. 

What is the average length of a single circuit t 

One hundred and seventy-five or two hundred 
miles. 

State in brief the course of the main current. 

Starting from one main battery, it passes along the 
wire, through the key and relay helices in each of¬ 
fice, through the intermediate main batteries, if there 
are any, to the terminal main battery ; thence it 


THE TELEGRAPH. 


43 


continues on to the earth by the ground wire, and 
through the earth back to the ground wire of the 
first battery, and by that to its starting place, and 
so on. 

Does the current really pass back through the earth ? 

Probably not, though the effect is the same as 
would be produced if it did so. 

What is the real explanation of this phenomenon ? 

The earth must be regarded as a reservoir of elec* 
tricity which yields up to one end of the line as muQji 
as it receives from the other. 

What is the advantage of employing the earth as a part 
of the circuit ? 

It saves the trouble and expense of an additional 
wire for the return current. Also, since the earth 
opposes no resistance to the transmission of electric¬ 
ity, the battery power thus required for a given dis¬ 
tance is only half of what would be necessary if the 
current were returned by a second wire. 


SECTION IX. 

The Local Circuit. 

Of what is the local circuit composed ? 

Chiefly of three parts. 

^lst. The metals and liquids of the local battery. 

2nd. The armature lever of the relay and the 
helices of the register or sounder. 

3d. Wires connecting these instruments and the 
battery. 

What wires are used for this circuit f 
Copper usually, because they conduct better than 
iron wire of equal size and are sufficiently strong for 
this purpose, strength not being needed as it is on 
the main line. 

How is the local circuit insulated ? 

Its wires are usually covered with some non-con¬ 
ducting substance as silk, cotton, or gutta percha, 
and the various parts of the instruments upon it are 
insulated as far as is necessary by being set in dry 
wood, or other non-conductor. 

How many battery cups are used on a local circuit ? 

Two generally, though one often is sufficient. 
What is the extent of this circuit ? 

Usually but a few feet, from battery to instrument; 
but in large offices the batteries are kept in a room 


ELECTRICITY. 45 

by themselves and then circuits leading to instru¬ 
ments are necessarily longer. 

State the course of the local current. 

Starting from the battery, it flows along the wire, 
through the armature lever of the relay, and the he¬ 
lices of the register or sounder, then back to the 
battery, and so on. 


SECTION X. 

The Key. 

[The four instruments whose description immediately 
follows belong to the common telegraphic system invent¬ 
ed by Prof. Morse. There is an almost endless variety 
of contrivances for transmitting and receiving messages, 
involving different applications of electric and chemical 
science. Among them may be prominently named Bain’s 
Electro Chemical and House’s Printing Telegraph, for 
descriptions of which the student is referred to larger 
treatises.] 

What instrument is employed in transmitting messages? 
The key. 

What is the hey ? 

A contrivance for opening and closing a Voltaic 
circuit at pleasure. 

Describe its construction. 

It is made in a great variety of forms as is every 
telegraphic instrument. But its essential parts are 
two metallic conductors insulated from each other 
and a movable bar called the key lever. The frame 
of the key usually constitutes one of these conductors, 
and the other is a small metallic piece passing 
through this frame and separated from it by bone- 
rubber or other non-conductor. 

With what are these conductors connected ? 

One with one part and one with the other part of 
the main circuit. 


THE TELEGRAPH. 


47 


How are they related to the hey lever ? 

The lever is so situated that it always connects 
with one of them, and may by a slight movement 
connect also with the other, thus joining the two 
and closing the circuit. 

How is this accomplished ? 

By means of two platinum pieces called the ham¬ 
mer and anvil. The hammer is attached to the 
lever and so connects with one part of the key ; the 
anvil is immediately below this and attached to the 
other part of the key. When the lever is depressed 
these pieces are brought into contact and the circuit 
is closed. 

How is the circuit opened again ? 

By a spring which raises the key lever as soon as- 
the pressure is removed. 

What is the circuit closer f 

A movable bar so situated that it may be made to> 
establish a permanent communication between the 
separated parts of the key. 

This description applies to the circuit closer, when it 
is made a part of the key. Sometimes, however, it is de¬ 
tached from the key entirely. It then operates by cut¬ 
ting the key off from the circuit when the latter is re¬ 
quired to be continuously closed. 


SECTION XL 
‘ The Relay, 

What is the relay in Morse's telegraph f 

An instrument whose office is to connect the main 
and local circuits in such a manner that the opening 
and closing of the former opens and closes the latter. 
Does the relay cause any communication of electricity 

between the two circuits ? 

It does not: It establishes between them a me¬ 
chanical and not an electrical connection. 

What are the essential parts of the relay ? 

They are as follows : 

1st. Two helices of insulated wire enclosing two 
bars of soft iron, or the two ends of one bar bent iu 
the form of a U magnet. 

2nd. A soft iron armature attached to a movable 
lever and situated near the ends of the soft iron bar 
or bars. 

3d. Two platinum points, so situated, one of them 
being fixed upon the movable lever, that the move¬ 
ments of that lever may separate or unite them. 

State the electrical connections of the different parts of 

the relay. 

Its helices connect with, and form part of the main 
circuit. 

The platinum points connect similarly with the 
local circuit. 


THE TELEGRAPH. 


49 


Explain the action of the relay. 

When a current traverses the main circuit it pass¬ 
es through the relay helices, and transforms the soft 
iron bars within them into electro-magnets ; the lat¬ 
ter then attract the armature which thus moves the 
armature lever and brings the platinum points into 
contact, closing the local circuit. 

When the main current ceases, the electro-magnets 
cease to attract the armature, which is then thrown 
back by a spring, separating the platinum points and 
opening the local circuit. 

iShould the armature be brought into contact with the 

poles of the magnets f 

It should not, for the residual magnetism would 
then prevent its being thrown back when the main 
current ceased. 

How is this prevented ? 

By screws which regulate the play of the armature 
in either direction. In some instruments also, the 
magnet itself is thrown forward or backward by a 
screw so as to accommodate its position to that of 
the armature. 

What is the adjuster ? 

A contrivance for regulating the tension of the 
spring which draws back the armature. 

For other parts of the relay see Section XIII. 




4 


SECTION XII. 

The Register and Sounder. 

What instruments are employed in receiving messages f 

The register and the sounder. 

Wherein do they differ ? 

In the fact that the former records the messages 
upon ribbons of paper, while the latter does not, the 
click of the instrument indicating the message 
to the ear of the operator. 

What are the essential parts of the register ? 

They are, 

1st. Two helices with their electro-magnets sim¬ 
ilar to those of the relay, but less powerful. 

2d. An armature attached to a long lever armed 
with a point for indenting the paper. 

3d. Clock work for steadily moving the paper in 
such a position as to expose it to the strokes of the 
writing point, or pen. 

Explain the operation of the register. 

When the local current is in action, the armature 
is attracted toward the electro-magnets, as in the re¬ 
lay. This moves the pen lever, pressing its point 
against the paper and indenting it into a groove in 
the cylinder under which it is passing. This con¬ 
tinues until the 1 circuit is broken, when a spring 
withdraws the point and the indentation ceases.— 


THE TELEGEAPH. 


51 


The mark thus impressed upon the paper may be 
long or short, according to the duration of the cur* 
rent. 

How are letters and figures indicated ? 

By long and short marks, commonly called dash* 
es and dots, or by combinations of them. 

For the Morse Alphabet see Sec. XVIII. 

Explain the construction of the sounder . 

It is similar to the register, excepting that it has 
no recording apparatus. 

For other parts of these instruments see next section. 
In what respects besides those already mentioned do the 
register and sounder resemble the relay ? 

In them as in the relay, the armature must be 
kept from contact with the electro-magnets, in order 
to avoid the effect of residual magnetism ; also, an 
adjuster is necessary in each instrument to regulate 
the tension of the spring attached to the armature 
lever. 


SECTION XIII. 

•The Relay Sounder. General Statements. 
What is the relay sounder ? 

An instrument used in receiving messages on lines 
which employ no local circuit. 

Horn does it differ from the ordinary relay t 

In having a more powerful electro-magnet and no 
local circuit connections. 

Is there any registering apparatus which may he worJced 
ly the main current t 

No such instrument is in general use, though one 
has recently been invented. 

What are the advantages of operating by sound f 
There is less difficulty in adjusting the instrument, 
and business is done more rapidly and with less li¬ 
ability to error. 

What contrivances besides the essential parts named be¬ 
long to the instruments previously described t 
Screws for regulating the play and bearings of 
movable parts, and screw cups to receive the circuit 
wires. 

Hoio many of the latter has each instrument ? 

Two, excepting the relay, which has four, because 
it connects with two circuits. 

An instrument has recently been invented by which 
messages may be transmitted simultaneously in opposite 
directions upon the same wire. Should this invention 
prove fully successful, the practical development and 
application of the principle on which it is based promises 
to mark a new era in the progress of the telegraph. 


SECTION XIV. 

Switches, Switch-boards, Ground Wires and 
Lightning Arresters. 

In addition to the instruments already described, what 
other contrivances are usually employed upon a tele¬ 
graph line t 

Switches or cut-offs, switchboards, ground wires, 
lightning arresters, and some others. 

What is the switch f 

A contrivance designed to change the course of 
the electric current by making new circuit connec¬ 
tions. 

Switches and cut-offs are mad8 in a variety of forms to© 
great to be described here. They are all very simple, 
however, and easily understood upon inspection. 

What is the most frequent application of this instrument? 

To throw the relay and key into or out from the 
main circuit. 

Mention other applications of it. 

To throw the ground wire on or off, to change the 
current from one line to another, etc. 

What is the switch-board f 

A combination of switches adapted to form various 
combinations of several different circuits. 

What is the ground wire ? 

A wire so situated that it may at pleasure be made 
to connect the line with the earth. 


54 theoretical telegraphy. 

How is the ground wire connected with the earth ? 

Generally by having its lower extremity attached 
to a plate of iron or copper buried sufficiently deep 
to reach moisture ; or it may be dropped into a well 
or stream of water. In city offices, however, the 
ground wire commonly is simply attached to water or 
gas pipes. 

How many ground wires are there on a line ? 

As many as offices ; each office has one. 

Are they always in connection with the circuit f 

The terminal ground wires only are always con¬ 
nected. The others are never used except when 
the line is out of order, or when it is desired to work 
a part of it alone. 

What is the paratounerre or lightning arrester ? 

It is a contrivance designed to protect the tele¬ 
graphic instruments from the effects of heavy charg¬ 
es of atmospheric electricity which sometimes traverse 
the line. 

For the cause of these discharges and for their effect 
upon the relay see Sec. XVII. 

Upon what principle is it constructed ? 

Upon the principle that atmospheric electricity, 
possessing a high tension, prefers to overleap a slight 
break in order to reach the earth by a short conduc¬ 
tor, rather than to traverse a long circuit. 

Of what does it frequently consist ? 

Of two metallic plates whose surfaces are separat¬ 
ed by very thin paper. One of these plates connects 
with the ground wire, and the other with the main 
line near the relay. 


THE TELEGRAPH. 


55 


Explain its operation. 

The instrument being constructed in this or some 
similar manner, the resistance of thin paper is all 
that prevents communication between the line and 
the earth. This resistance the ordinary Yoltaic 
current is unable to overcome and hence is obliged 
to keep on in the main circuit. But on the other 
hand, a discharge of atmospheric electricity passing 
along the line and reaching the lightning arrester, 
breaks through the paper between its plates, and 
enters the earth by the ground wire, thus being di¬ 
verted from the relay. 

Mention another form of this instr ument . 

Instead of the upper plate, weights are often em¬ 
ployed, connected with the line, and resting upon 
tissue paper on the plate which communicates with 
fche earth. 

This is a very convenient form of the instrument, and 
probably the most frequently employed. 


SECTION XV. 

The Galvanometer, Rheostat, Electric Varia¬ 
tor and Repeater. 

What is the galvanometer or galvanoscope f 

It is an instrument designed to measure or detect 
the presence of Voltaic electricity. 

The galvanometer is applied to a great variety of uses 
in connection with electrical science, and many of them 
are quite complicated. Its office, however, in the tele¬ 
graph, as well as the form of the instrument there em¬ 
ployed, is exceedingly simple. 

Explain the construction of the galvanoscope as employ¬ 
ed in the telegraph ? 

It consists of a simple magnetic needle freely sus¬ 
pended, popularly called a compass. When brought 
near a Voltaic current it tends to place itself at right 
angles to the direction of that current. 

For what purpose is it employed ? 

To show the presence of a current upon the line. 
For this purpose it is placed near the relay helices 
and when a current is passing, it is thrown aside 
from its natural northerly and southerly direction 
and thus by its movement manifests the presence of 
the current, even when the relay fails to do so. 

How does the galvanoscope show when the line is in op¬ 
eration ? 

By the violent agitation into which it is thrown by 
the repeated cessation and renewal of the current. 


THE TELEGRAPH. 57 

What direction should the relay helices have when used in 
connection with the galvanoscope ? 

An easterly and westerly direction. 

Upon most lines, the galvanoscope is dispensed with. 
In such cases, a careful adjustment of the relay is de* 
pended upon to show when the line is in operation. 

What is the rheostat ? 

An instrument designed to regulate the intensity 
ot Voltaic currents. 

How does it accomplish this object ? 

By introducing into the circuit a fine wire con¬ 
ductor offering a certain resistance to the passage of 
electricity. 

What is meant by such expressions as a fifty mile, one 
hundred, or two hundred mile rheostat ? 

Such expressions refer to rheostats that introduce 
into the circuit a resistance equal to that of fifty, one 
hundred or two hundred miles respectively, of ordi¬ 
nary line wire. 

For one application of the rheostat see Sec. VIII.— 
Others we have not space to mention. 

What is the electric variator f 
It is an instrument so contrived as to oppose to 
the passage of the current a greater or less resistance 
at the pleasure of the operator. 

This instrument is not employed on business lines. In 
the instruction of operators, however, it serves an ad¬ 
mirable purpose by producing variations in the working 
force of the current similar to those exhibited upon a 
long line. And when it is so connected with a wind vane 
as to be operated by the currents of the atmosphere, it 
reproduces perfectly the phenomena of a common tele- 
graphio line, thus affording students ample practice in 
the difficult matter of adjustment. 


58 


THEORETICAL TELEGRAPHY. 


What is the repeater ? 

It is an instrument designed to transfer a mes¬ 
sage directly from one circuit to another, thus avoid¬ 
ing the necessity of its being re-written by an ope¬ 
rator. 

How does it connect the circuits upon which it is em¬ 
ployed ? 

It establishes between them a mechanical con¬ 
nection of such a nature that one circuit by opening 
and closing opens and closes the other, 
j Does it cause any communication of electricity between 
the two circuits ? 

It does not. 

What can you say of its construction ? 

It is often very complicated in its structure ; too 
much so to be well understood without thorough ex¬ 
amination. When employed in an office entered by 
several lines, it is so arranged with switches as to 
eonnect any two lines desired. 

What is necessary in the operation of this instrument ? 

It is necessary that its several relays should be 
very carefully adjusted. 


SECTION XVI. 

Telegraphic Accidents. 

What are the leading accidents to which the telegraph is 
liable ? 

Breaks, escapes or ground connections, and crosses. 
What is a break ? 

Any accidental rupture of the line. 

How may breaks be classified ? 

Into three kinds, as follows : in the 
1st class, neither of the ruptured ends communi¬ 
cate with the earth, in the 
2nd, one end communicates with the earth, in the 
3d, both ends communicate with the earth. 

What follows a break of the first class f 
A total suspension of current throughout the en¬ 
tire line. 

What of the second class ? 

Suspension of current on that end of the line which 
does not communicate with the earth. The other 
end forms a short circuit. 

What is the effect of a break of the third class ? 

Each end of the line forms a short circuit. 

How is a break manifested ? 

By the refusal of the line to work its entire length. 

What is an escape ? 


60 


THEORETICAL TELEGRAPHY. 


Such a connection of the line with the earth that 
a part or all of the current escapes. 

Bow many kinds of escapes are there ? 

Two, partial, when a part of the current escapes 
into the earth, and total, when it all does. 

What is the effect of a total escape f 
As in the case of a break of the third kind, each 
part of the line forms a short circuit. 

What of a partial escape? 

A key in any part of the circuit can not fully con¬ 
trol the current beyond the escape j hence messages 
are transmitted over the escape with greater or less 
difficulty, according to its magnitude. 

What is a cross f 

Any accidental communication between two or 
more lines allowing their currents to intermingle. 
Between what lines does it generally occur 1 

Between lines running together along the same 
set of poles. 

What is the effect of a cross ? 

The lines connected by it refuse to work inde¬ 
pendently ; or, in other words, the current on each 
line is not properly controlled by the key, being more 
or less influenced by the current on the line or lines 
connected with it by the cross. 

How may business be conducted on one of the lines so 
connected t 

By opening all the others. The line not opened 
will then operate as if there were no cross. 


THE TELEGRAPH. 61 

Is it necessary that different parts of the same line should 
he used on opposite sides of the cross 1 
It is not, provided the intercommunication of the 
lines he perfect or nearly so ; for in that case, even 
if parts of different lines be employed, the cross will 
in effect unite them into one. 

What general principle may he observed in regard to any 
telegraphic accident which diverts from the line either 
all or a part of the current t 

That between either main battery and the place of 
•such accident, the line will work perfectly with the 
use of the ground wire, and often without it. 

There is frequently an exception to this rule in case of 
those accidents which take place near a terminus of the 
line. In such cases, the distance between the place of 
the accident and the remote terminus is often too great 
to be worked with advantage by a single battery. 

The manner of locating and repairing these accidents 
falls properly under the head of practical telegraphy and 
hence is not considered here. 


SECTION XVII. 

Atmospheric Electricity. 

Does the electrical condition of the atmosphere produce 
any effect upon the telegraph f 

It does, often causing heavy charges of electricity 
to pass along the line. 

How are these charges occasioned ? 

By such disturbances of the atmosphere that the 
latter becomes heavily charged with electricity in 
certain localities. The telegraph wires take up large 
portions of this electricity and transmit it along the 
line to the terminal ground wires where it is dis¬ 
charged into the earth, unless it be previously dis¬ 
charged by lightning arresters or some ground con¬ 
nection. 

When are such discharges most frequent f 

During, or immediately before thunder storms. 
What is their effect upon the relay instrument ? 

They often injure or destroy its helices by melting 
its wires or burning the insulating material which 
covers them. 

What are electric storms 1 

Atmospheric disturbances which cause waves of 
electricity to traverse the line in rapid succession. 
What is the effect produced upon lines by the aurora 
borealis or Northern light ? 


THE TELEGRAPH. * 63 

It is similar to that of electric storms as above de* 
scribed. 

What precaution should be observed whenever such atr 
mospheric disturbances become serious f 
The instrument should be cut out from the line.— 
During thunder storms this precaution ought neves- 
to be neglected. 


SECTION XVIII. 

The Morse Telegraphic Alphabet. 


A — 

ALPHABET. 

J - 

S--- 

B - 

K- 

T — 

C - - - 

L - 

U--- 

D - 

M - 

v... 

E 

N —- 

W- — 

F- 

0 - - 

X- — 

G- 

P . 

Y - - ■ 

H- - - * 

Q - 

z-.- 

I-- 

R - - - 

&- - 

*_ 

NUMERALS. 

6 - 


2- 

7- 

--- 

3- 

8- 


4- 

9- 

— 




0 — 

PUNCTUATION. 


Period - --- Emphasis- 

Semicolon- Parenthesis- 

Exclamation-Comma - — - — 

Quota --—-Interrogation 










xnsrixEis:. 


Alphabet, ... 

. 64 

Attraction, Electrical, Law of, 

10 

Aurora Borealis, 

15 

Battery, 



Leyden or Electric, 19 ; Galvanic 

or Voltaic, 24; 

Daniell’s, 23; Grove’s, 30 ; Electropoion, 32 ; 

Law for Connections of, 27. 


Break, .... 

59 

Circuit, 


Main, 40 ; Local, 44 : Relation to Instruments, 38 

Conduction and Conductors, 

. 12 

Cross, .... 

60 

Diamagnetics, 

. 34 

Electric Machine, * 

17 

u Storms, 

. 62 

“ Variator, 

57 

Electricity, 


Character of, 9; Properties of, 9 

; Divided into 

Positive and Negative, 10; Otherwise divided, 11 ; 

Motion of, 11; In Nature, 14; 

Frictional, 16 ; 

Voltaic, 23; Atmospheric, 62. 


Escape, .... 

59 

Galvanometer, or Galvanoscope, 

. . 56 

Ground Wire, 

. 53 

Induction, 

. . 13 


o 



66 INDEX, 


Insulation, .... 

13 

Insulators, Wade, 

. 40 

Key, .... 

46 

Leyden Battery, 

. 19 

“ Jar, 

18 

Lightning, 

. 14 

u Arrester, 

54 

“ Rod, 

. 20 

Magnet, 


Properties, of, 33; Natural or Load 

Stcne, 33 ; 

Electro, 35. 


Magnetics, 

34 

Magnetism, How Induced, 

. 34 

11 How Destroyed, 

36 

Non-conductors, 

. 12 

Register, .... 

. 50 

Relay, ..... 

. 48 

Relay Sounder, 

52 

Repeater, ... 

. 58 

Rheostat, .... 

57 

Sounder, .... 

. 51 

Switch, «... 

53 

Switch-board, .... 

. 53 

Thunder, . . 

14 

Variator, Electric, 

. 57 




CALKINS, GRIFFIN & CO.’S 

TIN ION 



OBERLIN, OHIO. 


STORES S. CALKINS, 
CHAS. .P GRIFFIN, 
CHESTER H. POND, 
DWIGHT A. CUSTISS, 


Proprietors. 


? 


BUSINESS DEPARTMENTS, 

complete, and fitted up without regard to expense 
with Banks and Offices in which different kinds of 
Business, and manner of keeping the various kinds 
of Business Account Books are fully illustrated. 
Everything belonging to any department or branch 
of Business Education is thoroughly and satisfactory 
ally taught. 

A Teachers’ Class in Spencerian Penmanship is 
a feature of the Chirographic Department which 
affords superior advantages to those desirous of pre¬ 
paring for Teaching. The Tuition Fee is only about 
ONE HALF that usually charged in similar Insti¬ 
tutions ; while the advantages of the place, and the 
comparative absence of temptations to vice, are im¬ 
portant considerations. 

Oberlin is situated on the C. & T. R. R.—30 miles 
west of Cleveland; and has been formany years distin- 


guished for its morality, good order and religious 
influences-. It has a population of about 4,000 peo¬ 
ple, but has not a single dram shop—gambling or bil¬ 
liard saloon. 

Some people—strangely enough—suppose that a 
Business Education can be better acquired in a Col¬ 
lege building, located in a large city, than in the 
same College building if removed out of the city, to 
a pleasant, quiet village, comparatively free from 
temptations, vices and those almost numberless 
things that withdraw the attention of the student 
from his studies. Other people, there are, however, 
who believe that the freer from city attractions, temp¬ 
tations and inducements to squander money the bet¬ 
ter for those who are—perhaps for the first time, sep¬ 
arated from friends and home influences. 

To any who have doubts concerning where to go 
for a Business Education, we say—if you study one 
week with us, and find we have deceived you by false 
representations, ask for your tuition fee, and it will 
be refunded. 

Remember, we are not a “link” in any body’s 
chain, neither do we lay claim to so absurd a thing 
as a u 'patent ’’ on a system of instruction. 

Do not fail to send for Catalogue and Circular 
before going elsewhere. 

Address as above. 


TELEGRAPHIC DEPARTMENT. 


Faculty and Teachers, 

IN TELEGRAPH DEFRTMENT. 

CHESTER H. POND, 

Principal and Professor of Practical and Tneoretical 
Telegraphing, and Telegraphic Bookkeeping. 

C. N. POND, 

Assistant Principal and Professor of Practical and 
Theoretical Telegraphing, Frictional and Voltaic 
Electricity, Electro Magnetism, &c., &c. 

Dr. JAMES DASCOMB, 

(Professor in Oberlin College, and Charity Medical 
College, Cleveland, 0.) 

Lecturer on Chemical Electricity. 

Rev. CHAS. H. CHURCHILL, 

(Professor in Oberlin College.) 

Lecturer on Frictional Electricity. 

A. C, RIDEOUT, Miss LALIE COLE, 
Tutors. 




-AJDVISOIR/Sr BOARD. 

FOR TELEGRAPH DEPARTMENT. 

J. H. WADE, 

President Western Union Telegraph Co., and Pacific 
Telegraph Co. 

Hon. J. D. CATON, 

President Illinois & Mississippi Telegraph Company. 
0. H. BOOTH, 

Superintendent P. F. W. & C. R. R. Telegraph Co. 
Wm. KLINE, Jr., 

Sup’t. M. S. & N. I. R. R, Telegraph, Toledo, 0. 

A. C. FRY, 

Superintendent S. D. & C. R. R. Telegraph Line. 
J. S. LYLE, 

Superintendent Telegraph, Covington, Ky. 

The throughness and prosperity of this Telegraphic 
School are evinced by the following facts : 

1st. The number of students in attendance dur¬ 
ing the year ending April 20, 1866, was one hund¬ 
red and thirty-six. 

2d. During that time a large number of experi¬ 
enced operators have examined the arrangements 
and appliances of the Institute and pronounced them 
complete. 

3d. The course of instruction is under the super- 


vision ot an Advisory Board composed of the Presi¬ 
dents of two leading Telegraph Companies and four 
Telegraph Superintendents, and is under the imme¬ 
diate control of Practical Telegraph men, who are 
Principals of this Department. 

4th. Testimonials of the most satisfactory charac¬ 
ter from many prominent Telegraph men are on file 
at the Institute office and can be examined by any 
one who desires. 

5th. Superintendents and operators are constantly 
sending to the Institute those persons who apply to 
them for instruction. 

6th. Operators, having brothers and sisters who 
desired to learn telegraphing, have in repeated in¬ 
stances, sent them to the Union Institute, rather 
than attend to their instruction themselves in their 
own office, thus practically evincing their confidence 
in the thoroughness of the Institute Telegraphic 
Course. 

7th. More than this, persons already qualified as 
paper operators, and some who have actually served 
as such on telegraph lines have resorted to the Insti¬ 
tute for sound drill, and testified from their own ex¬ 
perience that the facilities of the Institute in this 
respect are superior to those of any business office 
or other Telegraphic School. 

Read these facts and draw your own inferences. 
It is not claimed that this is the only good school of 
the kind, but that in real excellence it much surpas¬ 
ses most and is surpassed by none. In short, in all 
that renders such a school complete and useful, the 


Telegraphic Department of the Union Business Insti¬ 
tute invites comparison with other similar schools 
and challenges competition. 

Do not fail to send for Circular before going to any 
other Telegraph Institute; for we are certain that when 
all the advantages of this school are fully understood 
it will receive the undivided patronage of the Public, 









LIBRARY 














